David C. Ditsch

A review of soil erosion potential associated with biomass crops

Abstract It has been estimated that up to 60 million hectares could be devoted to energy crop production in the U.S. Due to economic considerations, biomass crops will probably be produced on marginal cropland which is frequently highly erodible. Thus, the impact of herbaceous and woody biomass crop production on soil erosion must be addressed. Perennial grasses provide year-round soil cover, limiting erosion even with continued biomass harvest. Vigorous perennial herbaceous stands reduce water runoff and sediment loss and favor soil development processes by improving soil organic matter, soil structure and soil water and nutrient-holding capacity. Minimum tillage management of row crops reduces erosion compared with systems involving more frequent or more extensive tillage. Woody biomass plantations reduce water erosion by improving water infiltration, reducing impacts by water droplets, intercepting rain and snow and physically stabilizing soil by their roots and leaf litter. Shelterbelts reduce wind erosion when planted as shelterbelts and improve soil organic matter, soil structure and soil moisture in their leeward zone, reducing soil erodibility. Harvesting of woody biomass plantations may be accompanied by increased erosion. Forestry clear-cutting, especially on steep slopes, often results in a large increase in water erosion. For this reason, it is essential that woody biomass plantations be designed for rotational harvesting, even though this may result in higher harvesting costs.

Endophyte Infected Tall Fescue and Small Ruminant Production: Do We Have a Problem?

Small ruminant production has been expanding in the upper transition zone where tall fescue [Lalium arundinaceum (Schreb.) Darbysh.] is the dominant perennial cool-season grass forage species. Although the grass is well adapted to the region, an endophyte (Neatyphadium caenaphialum) that infects most tall fescue plants produces ergot alkaloids, which can cause a toxicosis in cattle that negatively affects reproductive performance and weight gain efficiency. Limited research with sheep indicates a negative impact of ergot alkaloids on physiology and production, but even less research has been done to determine effects of ergot alkaloids on meat goat physiology and production. A better understanding of the influences that ergot alkaloids have on small ruminant growth and development, and reproduction will be needed before management approaches can be developed to reduce or alleviate tall fescue toxicosis.

Establishment of kura clover and red clover on surface mine spoil and soil

ABSTRACT Field trials were conducted to study edaphic and seed treatment effects on stand establishment of kura clover (Trifolium ambiguum Bieb.) compared with red clover (T. pratense L.) on surface mine spoil and undisturbed soil. Scarified kura clover seed were either left uncoated, coated with a commercial seed treatment, or coated and treated with a fungicide. Site effects on seedling stand density were small. Maximum red and kura clover stand densities near 60 and 30 plants m−1 of row, respectively, represented 53% and 33% of the germinable seed planted. In June following seeding, shoot mass of red clover was 13.6 and 4.1 times greater than that of kura clover on soil and mine spoil, respectively. Seed coating effects were small. One-yr-old kura clover plants from the soil site had greater root, crown and total plant mass plant−1 than red clover but the opposite was true on mine spoil. The consistency of reduced seedling densities for kura compared with red clover suggests that higher seeding rates m...